Unity Temple Unitarian Universalist Church is a liberal congregation with membership in the Unitarian Universalist Association. The building was designed by Frank Lloyd Wright, and is worth a visit in itself.
The congregation is well-established in the Oak Park area. It's a little difficult to meet people at first, as everyone seems to know everyone else. But joining one of their many classes or taking part in an activity offers the chance to get to know other members.
If you're looking for liberal theology, or just a place to get that sense of community without a lot of "preachyness", this is the place for you! And if you aren't already familiar with Unitarian Universalist churches, check out the website. You'll find they aren't traditional Christian churches, but more like liberal religious communities.
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